The United States announced economic sanctions against Russia on Thursday and the expulsion of 10 diplomats in retaliation for what Washington says is the Kremlin's US election interference, a massive cyber attack and other hostile activity.
President Joe Biden's executive order "sends a signal that the United States will impose costs in a strategic and economically impactful manner on Russia if it continues or escalates its destabilising international action," the White House said.
The moves are in response to alleged interference in last year's presidential election as well as the hacking last year of federal government agencies. The US for the first time explicitly linked that intrusion to a Russian intelligence service.
The sanctions have been foreshadowed for weeks by the administration and represent the first retaliatory action announced against the Kremlin for last year's hack, familiarly known as the SolarWinds breach.
In that intrusion, Russian hackers are believed to have infected widely used software with malicious code, enabling them to access the networks of at least nine agencies in what US officials believe was an intelligence gathering operation aimed at mining government secrets.
Besides that hack, US officials last month alleged that Russian President Vladimir Putin authorised influence operations to help Donald Trump in his unsuccessful bid for reelection as president, though there is no evidence Russia or anyone else changed votes or manipulated the outcome.
A statement from the White House said the Kremlin made "efforts to undermine the conduct of free and fair democratic elections and democratic institutions in the United States and its allies and partners."
It also called out Russia's extraterritorial "targeting" of dissidents and journalists and undermining of security in countries important to US national security.
In Brussels, the NATO military alliance said US allies "support and stand in solidarity with the United States, following its 15 April announcement of actions to respond to Russia's destabilising activities."